In certain applications, for example, aircraft landing gears, a landing gear wheel and brake assembly may be retained by a nut (axle nut) and a washer. A landing gear in an aircraft is a structure that supports the aircraft on the ground and allows it to taxi, take off, and land. Typically, the aircraft has several landing gear units including nose landing gear (NLG) and main landing gear (MLG). Most configurations of the landing gear typically include wheels equipped with shock absorbers, brakes and other suspension components.
FIG. 1A illustrates an example of a main landing gear 10 on a commercial aircraft. The main landing gear 10 typically includes two or four wheels 11 mounted on a main gear truck assembly 12. FIG. 1B illustrates a detailed view of the main gear truck assembly 12. The main gear truck assembly 12 includes a plurality of axles 85 for mounting the wheels 11. To properly install the wheels 11 on the axles 85, a mechanic or other qualified ground crew personnel installs a washer 65 on the axle 85 before tightening an axle nut 70 to secure the wheel 11 and properly load wheel bearings. This ensures the proper alignment and rotation of the wheel 110 and prevent premature wear or friction, total wheel loss, among other potential problems. If a mechanic forgets to install the washer 65, the wheel 110 and landing gear wheel may fail to function properly, be damaged, damage the axle 85, landing gear and other structural components and hamper directional control of the aircraft
Currently, it is fairly easy for a mechanic to accidentally leave out the washer 65 during wheel changes. For example, typically, the washers 65 may get stuck to the old wheel 11 as a result of grease or dirt buildup. When a new wheel 11 is installed without a washer 65, the axle nut 70 may still be tightened which makes it difficult for the mechanic to detect the faulty installation. Further, since the axle nut washer 65 is located between the wheel 11 and nut 70, the missing component may be difficult to detect visually or by feel. Damage that results from such faulty installations may lead to unsafe conditions, require costly repairs, which leads to aircraft downtime. Furthermore, with regard to safety, improper installation of these components may result in monetary and other fines from regulatory agencies, and even worse, may result in the wheels being separated from the axle leading to costly accidents during landing or take off of the aircraft.
Even though the above-mentioned faulty installations are described in the context of aircraft landing gears, one of ordinary skill in the art can understand and appreciate that such faulty installations of wheels without the washer may occur in any other type of vehicle as well. For example, such faulty installations may also occur in automobiles such as cars, jeeps, etc. Therefore, there is a need for a fastener that overcomes the above-mentioned shortcomings of conventional technology.